Narrative:

I was working a busy session in a low altitude sector that serves newark arrs plus other overflt traffic. Was distracted by a sequence problem in the northwest part of the sector while the conflict developed in the southern part of the sector. Side conversations at an adjacent sector also broke my concentration. I recognized the conflict between descending medium large transport X and light transport Y and issued control instructions, but separation was already lost. For reasons yet to be determined, the conflict alert feature of the host computer did not activate. This reinforces in my mind that I may be too dependent on the computer to find conflicts, and that I must maintain a good scan and not be complacent about conflicts the computer doesn't recognize.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION WHEN ACR MLG X IS ALLOWED TO DESCEND INTO CONFLICT WITH ACR LTT IN CRUISE AT 12000.

Narrative: I WAS WORKING A BUSY SESSION IN A LOW ALT SECTOR THAT SERVES NEWARK ARRS PLUS OTHER OVERFLT TFC. WAS DISTRACTED BY A SEQUENCE PROB IN THE NW PART OF THE SECTOR WHILE THE CONFLICT DEVELOPED IN THE SOUTHERN PART OF THE SECTOR. SIDE CONVERSATIONS AT AN ADJACENT SECTOR ALSO BROKE MY CONCENTRATION. I RECOGNIZED THE CONFLICT BTWN DSNDING MLG X AND LTT Y AND ISSUED CTL INSTRUCTIONS, BUT SEPARATION WAS ALREADY LOST. FOR REASONS YET TO BE DETERMINED, THE CONFLICT ALERT FEATURE OF THE HOST COMPUTER DID NOT ACTIVATE. THIS REINFORCES IN MY MIND THAT I MAY BE TOO DEPENDENT ON THE COMPUTER TO FIND CONFLICTS, AND THAT I MUST MAINTAIN A GOOD SCAN AND NOT BE COMPLACENT ABOUT CONFLICTS THE COMPUTER DOESN'T RECOGNIZE.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.